A method and system for secure processing of authentication key material in an ad hoc wireless network enables secure distribution of the authentication key material between a mesh authenticator (110) and a mesh key distributor (115), which may be separated by multiple wireless links. The method includes deriving a pairwise transient key for key distribution (PTK-KD) using a mesh key holder security information element (MKHSIE). A mesh authenticator pairwise master key (PMK-MA) is then requested using a first mesh encrypted key information element (MEKIE) that includes data origin information. Using the pairwise transient key for key distribution (PTK-KD), a second mesh encrypted key information element (MEKIE) is then decrypted to obtain the mesh authenticator pairwise master key (PMK-MA).